Life is what molecules eventually​ do on the habitable planets

Planets were created as the byproducts of stars. They inherited atoms from birth and death of stars. These atoms reacted. They made molecules including the most abundant molecule – water. All the water got evaporated from the hotel planets. The cooler ones lived in the ice ages. Some planets like earth could retain water. Heavier planets retained their atmosphere due to gravity. Air escaped into space on lighter ones. We on earth are lucky to have the oceans and the atmosphere. But, even our earth was not habitable in its formative stage. Some of the molecules that make me and you today were swimming in the ocean in the myriad of forms at that time. Some of them were flowing in the rivers, settling in the sediments, rising in the mountains, or clashing in the tectonic plates, or drifting with the continents. In those times, we all were erupting from volcanos, thundering in the sky among the clouds of not only water but all of the strange liquids we now sample in the bottles in our chemistry labs.

The molecules we identify as ours today were metamorphosing into all possible compounds documented in the chemistry books, both inorganic and organic. We were erupting, evaporating, boiling, blowing, raining, endlessly. There was no purpose. The earth was not arranging for the life to emerge out of this chemical soup. It was playing the whole game of geophysics and chemistry at the natural pace. The game continued for millions of year and then something significant happened according to our point of view. Life emerged. As for as the molecules that make us today are concerned, they had no point of view. They combined from simpler to the more complex combinations. Each new combination would open up the possibility of millions of newer combinations.

Our earth was not special: similar events might have unfolded on enumerable distant planets in the universe that are conducive to life. We are not alone in this universe. Who knows when which stroke of lighting produced first amino acid, or first RNA, or the first cell! Then, there were many such, replicating themselves, and improvising. The molecules that make us today, at that time, were living spread among millions of micro-organisms. Maybe, a part of you was at the north pole and another at the south pole. Every micro-organism responded to light or temperature or to some other molecules. Our emotions like desire and aversion can be traced back to these simple responses of the first living cells to the outside stimuli. These simple behaviors become more and more complex with time.

The micro-organisms replicated themselves, sometimes making replications errors. What we see today – the whole diversity of life – are the errors that were better equipped to survive. We do not see the other set of errors – less equipped to survive – due to the obvious reason that they didn’t survive long.

In that era, the molecules that make us today were living millions of lives, most of them wasted, but all necessary. Some of these life forms become more complex, multicellular. We developed organs. The first eye was just a pinhole camera: version 0.1. Then came version 0.2 which could tell few shades of lightness and darkness. Then, the resolution and color sensitivity improved with subsequent versions. Soon, life evolved out of oceans into the land. Gigantic animals like dinosaurs were evolved, sustained, and were destroyed on this earth. If we are the molecules that make our body, we have lived in dinosaurs as well. When a meteorite destroyed the dinosaurs, we were there exploding in the blast and settling in the dust.

We, as molecules that make our body today, evolved in myriad life forms, always adapting to the new situations and building up complexity out of random fluctuations. Many of our life forms became extinct. Many survive still. We grew on the earth as forests and oxygenated the atmosphere. We blossomed as flowers and flew as bees and birds. The human form that we take as our exclusive identity evolved only just a few thousand years ago in this cosmic journey spanning billions of years.